The host inflammatory process is associated with localized tissue injury. Patients who have undergone a stroke episode often have evidence of vascular tissue injury associated with host responses. Using a multi-analyte cytokine and growth factor panel, it is intended to study the natural history of host reactions in stroke victims in order to assess the role played by inflammatory factors in the severity of the disease. Additionally, the application of such panels will enable investigators to determine the pathways by which therapeutic interventions act.